you can just 'wait' or use fast travel to replenish your health and magicka, so the only reason for sleeping in a bed is to raise your level. Therefore, you can put off leveling up until you've raised those skills with the attributes you favor. You only need to really write that down if you're an obsessive-compulsive powergamer.

Granted, I am a minmaxer and if I waste character stats I feel bad. It's like…chosing a race on character creation you absolutely hate after the first hour and then always have the feeling you should start over.

But that aside: The "natural" way would be to rest whenever you get the message that you get a level up. But I think you agree that this is nothing you should do.
So instead you would save, rest, check your gains and load again.
But if you accumulate more skill gains which you would need, you also waste potential. Thing is, chosing an ability you would use most like a melee skill for a fighter is the worst thing you can do in Oblivion.
Nehrim fixed that.
Well, don't want to go into detail here, after all this thread is about Nehrim. If you want to dig deeper into the leveling problem you might want to read this: http://www.uesp.net/wiki/Oblivion:Le…veling_Problem